As an all singing, all dancing Toyota man, this will come off a little strange. But I actually agree with the call for a Jeep.
I'll start of by saying that I would never have purchased a Jeep if the 76 Series had come with airbags, ABS and traction control back in 2007. But nonetheless it didn't, and I ended up doing a "Jeep experiment".
I owned one (07 JK 4 Door Diesel) for 3 years and am glad I sold it before the warranty period expired, as you pay through the nose for parts on those things, but this was the most capable 4x4 I have ever owned* (Caveat - that statement only applies after the standard suspension was replaced with a ~50mm lift kit and some decent rubber was put on). This was a light car, great angles, nice looking, traction control etc etc etc. As for payload, with two coppers onboard, there would be plenty of room for gear. In light of the period of use of the Police, I'd suggest Jeep. If I was buying it for myself to keep for 20 years, I would never go past a Toyota though.
Cons - not as comfy as the Toyotas I've owned (particularly the 80 series-I loved that thing!).
I saw a Vic Police JK Wrangler a few years ago up at Falls Creek.
* this covers the JK, 40 series, 60 series, 79 series, 80 series, 110 Prado & now 150 Prado.